Clinically available reinforcing materials for soft tissue reconstruction

Regeneration capability of neonatal lung-derived decellularized extracellular matrix in an emphysema model

Impaired and limited alveolar regeneration upon injury advances pulmonary disorders and irreversibly affects millions of people worldwide. Adult mammals do not have a strong potential to regenerate functional lung tissues, while neonatal lungs robustly proliferate and regenerate the functional tissue within a week of birth upon injury. The differential composition of the extracellular matrix (ECM) of neonatal tissues favors cellular proliferation and migration, fostering lung regeneration. Regardless, conventional ECM therapies employ adult-derived tissues. Therefore, the potential differences in regenerative properties of adult and neonatal lung ECM were investigated using in vitro and in vivo lung emphysema model. Decellularization of the neonatal and adult lungs was performed using freeze-thaw cycle method. Decellularization process was structurally characterized using SEM and immunostaining. In vitro treatment of neonatal lung-derived ECM (NECM) significantly enhanced the cellular migration and proliferation compared to adult-lung derived ECM (AECM) treated cigarette smoke-extract (CSE)-stimulated A549 cells. Following the administration of AECM and NECM, we observed a significant decline in emphysematous features and an improvement in lung functions in NECM group. NECM treatment increased the ratio of HOPX+/SpC+ cells with an active proliferation in SpC+ cells shown by colocalization of SpC+/Ki67+ and SpC+/Brdu+ cells. Moreover, NECM treatment activated the Neureguline-1/Erbb2 signaling and fostered a regenerative environment by upregulating the expression of regenerative genes including FGF, WNTs and AXIN-2 as compared to AECM treatment. Our findings suggested the potential utilization of NECM as novel therapeutics in regenerative medicine, deviating from the conventional application of adult-derived ECM treatments in pre-clinical and clinical research.

A paradigm shift for diaphragmatic and chest wall reconstruction using a bovine acellular dermal matrix: an analysis versus synthetic meshes

OBJECTIVES

Recently, biologic meshes have gained increasing popularity in soft tissue reconstruction. The aim of this study was to investigate the use of a bovine acellular dermal matrix (SurgiMend, Integra LifeSciences, Princeton, NJ, USA) in diaphragmatic and chest wall reconstruction by comparing it with synthetic meshes.

METHODS

Consecutive patients who underwent diaphragmatic and/or chest wall reconstruction at a single center from 2016 to 2021 were retrospectively reviewed. Outcome measures included surgical site complications, readmission, and reoperation.

RESULTS

Sixty-six patients underwent diaphragmatic and/or chest wall reconstruction for a malignant (74.2%) or benign (25.8%) disease. SurgiMend was used in 26 (39.4%) patients and a synthetic mesh in 40 (60.6%) patients. There were no significant differences in baseline characteristics between the groups. Surgical site complications included prolonged air leak (12.1%), pleural effusion (9.1%), pneumothorax (3%), empyema (1.5%), and wound infection (1.5%). The patients in the synthetic mesh group developed a significantly higher rate of surgical site complications compared to those in the SurgiMend group (37.5% vs. 11.5%; p = 0.025). Similarly, the readmission rate was significantly higher in the synthetic mesh group (17.5% vs. 0%; p = 0.037), with causes including pleural effusion (n = 3), pneumothorax (n = 2), empyema (n = 1), and pneumonia (n = 1). Among the study cohort, only 1 patient with a synthetic mesh underwent reoperation (p > 0.99).

CONCLUSIONS

The use of surgiMend in diaphragmatic and chest wall reconstruction is associated with fewer surgical site complications and readmissions compared to synthetic meshes.

Fundamentals of Extracellular Matrix Biomaterial Assimilation: Effect of Suture Type on Attachment Strength and Cell Repopulation

The clinical results with extracellular matrix biomaterials are confounded by expectations of material response based on years of experience with permanent or degradable synthetic polymers. However, the remodeling or assimilation of extracellular matrix biomaterials is dictated by cell-mediated processes rather than fibrous encapsulation or hydrolytic degradation. Previously, we found that tissue adherence and revascularization were dictated by proximity with de-epithelialized host tissue. We now investigate the effects of polymer and fixation type on attachment strength and rate of cell repopulation in an intra-abdominal implant model.